1. #include <avr/io.h>
  2. #include <util/delay.h>
  3. #include <avr/interrupt.h>
  5. /******************************************************************************/
  7. int main(void)
  8. {
  9. cli();
  11. DDRD &= ~_BV(DDD0); // set as input
  12. PORTD |= _BV(PORTD0); // enable pull-up
  14. DDRB |= _BV(DDD5);
  15. PORTB |= _BV(PORTB5); // initialize to high
  17. PCICR |= _BV(PCIE2); // set PCIE2 to enable PCMSK2 scan
  18. PCMSK2 |= _BV(PCINT16); // set PCINT16 to trigger an interrupt on state change
  20. sei(); // turn on interrupts
  22. while (1);
  23. }
  25. /******************************************************************************/
  27. ISR (PCINT2_vect)
  28. {
  29. if (PIND & _BV(DDD0))
  30. PORTB |= _BV(PORTB5);
  31. else
  32. PORTB &= ~_BV(PORTB5);
  33. }
  35. /******************************************************************************/